Noobe Lager Fermentation Question

[Arminius757]

So this will probably fall under that whole "patience is a virtue young padawan" but I will ask anyway.
I am currently brewing my first lager, a "Bitburger" extract clone using the flowing recipe:
http://byo.com/malt/item/1798-bitburger-premium-clone
The only thing I changed is the yeast, I pitched two packs of dry yeast 34/70. Also, instead of following the fermentation schedule posted there, I did a little research and opted for the Tasty's lager fermentation schedule. Note that I also pitched the yeast at about 55, not the 68 mentioned in the above recipe. Brew day was on the 25th of Feb. So, after a very very long lag time of almost 72 hours, the beer finally got underway. I started checking the SG about every day or two so that i could keep up with the schedule. OG was 1.045, now at about 1.023, and with the help of Beersmith, I expect to get down to about 1.011-012. I use a refractometer, so its not like I am pulling out massive amounts of beer at a time to check. Also, the fermentor is inside a chest freezer with temperature control and the temp probe inside the beer via thermowell.
Basically, my question is as follows, how long should I expect this beer to ferment? I have been reading a lot of different things on lager fermentation, and I have seen things from saying from 10 days to 3 weeks. I was hoping to have my beer in secondary for lager by the end of the week as I am going out of town for about a week. The beer is about half way done, but I have noticed that the krausen has collapsed and is all but gone at this point... I guess I am worried about a stuck fermentation, as the SG hasnt changed all too much. So I just leave it till when I get back? I was hoping to have this beer done around the 10th of April. I know that means this is a short lagering cycle. I am just asking for some advice on what actions to take now.

Thanks

 

[GrogNerd]

refractometers are unreliable for reading SG once fermentation starts. use a hydrometer

although you can use a refractometer to check for CHANGES in gravity, the reading itself is meaningless without some conversion

rack to secondary for lager is optional, many do it in primary

leaving it for your return would not hurt, nor will a shortened lagering cycle

 

[m1k3]

10 days to 3 weeks is stated to cover the full range of ferm temps, OGs, yeast nutrients and O2 additions possible --- there are a lot of variables!

If your fermentation vessel is transparent enough you will see 34/70 drop to the bottom when it is done.

My process - other people do lagers different.

As soon as I see 1/4" of yeast flocked I start ramping up the temp a few degrees per day.

So, if this happens at day 7 at 50F in my wort at my temperature... I'll eventually get to 60F by day 10... and it is done. I'll let it sit until it gets darker in color (the yeast is dropping even more from the beer).

Then you know you are ready to cold crash or ramp down the temp to lager.

I never take gravity readings because I don't want to risk infection.
With a good ramp up (d-rest) process... it will hit terminal gravity every time.

By the way... this is how I do my ales too now. the temps are higher for ales but my process is exactly the same.

 

[Arminius757]

Thanks for the replies. I think I'll check the gravity later in the week and make a determination from there. I've been slowly ramping up the temp from 52 to about 58 now and I'll let it sit here for a few more days. If it's not a terminal gravity, I'll just let it sit for the week I'm gone then lager it when I get home. Other suggestions are still welcome. I use a bucket fermentor now and I can't quite look at it seeing that it's in the chest freezer.
Should I be worried about the fact that the krausen has already disappeared without reaching FG?
Also, for a good d-rest, what temp should I aim for? Tasty's has me reaching a final temp of 66 but I don't plan to leave it there for a week.

 

[Cyclman]

You can use this calculator with a refractometer. http://seanterrill.com/2012/01/06/refractometer-calculator/

It may not be as accurate as a hydrometer, but for me, I can tell when the beer is done, good enough for me.

 

[McKnuckle]

Should I be worried about the fact that the krausen has already disappeared without reaching FG?

Please don't ignore the brief comment about using refractometers for post-fermentation readings. You cannot do it without using corrective math. The reading will be much higher than the actual gravity once alcohol is present in the solution.

Use the second calculator here to convert the post-ferm refractometer reading to actual SG.

 

[Arminius757]

Geez thanks guys, turns out I never knew about this. Guess thats what makes me the noob huh?
Well with the calculations shown, I have reached terminal! So I think I will let it sit for a day or two at 62 for the d-rest, then put it in secondary later this week and cold crash it for lagering.
Thanks for all the help!